James a



(No Model.)

J. A. M'QALLISTER.

DUPLEX BRIGK.

No. 339,799. Patented Apr. 13, 1886-,

D C 37 O\ G O D WITNESSES WMQWZQ.

ATTORNEYS.

UNITED STATES JAMES A. MCALLISTER, or FRE'DnRIoroN, NEW BR'UNswIoK,

PATENT OFFICE.

OANA DA.

DUPLEX BRICK.

SPECIFICATION forming part of Letters Patent No. 339,799, dated April 13, 1886.

Application filed August 11, 1885.

To all whom it may concern.-

Be it known that I, JAMES A. MoALLIsTnR, of Fredericton, in the Province of New Brunswick and Dominion of Canada, have invented a new and Improved Duplex Brick, of which the following is a full, clear, and exact description.

My invention relates to the construction of brick or building-blocks; and its object is to construct a brick that can be easily made and handled, and which, when used, will produce a firmly-united wall that will be practically frost and moisture proof.

The invention consists of two or'dinarysized brick that are united by a connecting neck or web, thesurfaces of the brick being in-.

dented, for purposes which will be hereinafter specifically explained.

Reference is to be had to the accompanying drawing, forming a part of this specification, which is a plan view of a brick made in accordance with my invention.

My improved double or duplex brick consists of two blocks, A A, substantially in the form and proportion of an ordinary brick, and which are united by a neck or wel), B.

The upper and lower faces and the ends of the brick are formed with indentures C C, so that when the brick are built up in courses the mortar will enter said indentations and thereby obtain a firmer grip upon the brick. The parts A A being spaced, as shown, by the neck B, there will be a dead-air space in any Serial No. 174,116. (No model.)

wall built from such brick as have been dcscribed, which, as is well known, will render the wall practically frost and moisture proof.

Another advantage of my improved form of brick is, that it can be more easily made than two single brick, as it requires but a single handling and pressing to make it, and then, too, the brick-layer can build more wall in a day when using my brick than he could with the ordinary form.

I am aware of the brick forming the subjectmatter of Letters Patent No. 189,676, of April 17, 1877, wherein there is illustrated and de scribed a brick formed in two parts and united by a web, and designed to interlock when set up in a wall; and I make no claim to the subject-matter disclosed in said patent, my invention being confined to a brick which may be used to form a wall with a central airspace.

Having thus described my invention, I claim as new and desire to secure by Letters latent 1. An improved building-brick, consisting of the rectangular blocks A A, united by a neck, B, substantially as described.

2. An improved building-brick, consisting of the blocks A A, united by a neck, B, and formed with the indentations O C, substan tially as described.

JAMES A. MOALLTSTER.

Vi t n esscs:

W. F. CANTZ, XV. F. NIcrroLsoN. 

